Falaj 12: What Changed?

Comparing two versions of a file is one of the most useful skills in security work: a changed configuration, a modified script or an altered log can show exactly what someone did. The diff command prints the lines that differ between two files, marking lines from the first with one symbol and lines from the second with another.

Your home directory has an old and a new version of the same settings file. Several lines have changed, and most of the changes are ordinary. One of them contains the password for the next level. Read the differences carefully, decide which change is the interesting one, and take the value from it.

Do not simply print both files and compare by eye; let the tool find the differences for you. This is a simulated shell over invented files: it understands a teaching subset of commands, and help lists them. When you have the password for level 13, run login 13 <password> or paste it into the answer box.